Apparatus for cutting tire molds



' Nov. 30, 1937. l.. M. WATSON ET A1. 2,100,461.;

APPARATUS FOR CUTTIG TIRE MOLDS Filed Occ. ll, 1935 5 Sheets-Sheet iToRNEY v Nov. 30, 1937. .1.. M '.WATSON ET Al. 2,100,461

APPARATUS FOR CUTTING TIRE MOLDS I Filed Oct. l1, 1935 5 Sheets-Sheet 2Nov. 30, 1937. ;M. wAToN ET AL APPARATUS FOR CUTTING TIRE MOLDS l 5Sheets-Sheet 5 Filed Oct. ll, 1935 INVENTOR` Aszf M. m4

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Nov. 3o, 1937.

. L. M. WATSON ET AL APPARATUS FOR CUTTING TIRE MOLDS Filed ot. 11, 19555 Sheets-Sheet 4 IN V EN TORS `Nov- 30, 1937. 1 M. WATSON ET ALAPPARATUS FOR CUTTING TIRE MoLDs Filed oct. 11, 1955 5 sheets-sheet 5Patented Nov. 30, 1937` Y i Y 2,1%,451y

PATENT OFFICE 7 APPARATUS For. CUTTING TIRE Moms Lisle M. Watson andRaymondrF. Ternes, Detroit, Bch., and Lester G. Budlong, Mount Vernon,

N. Y., Products, Inc., of Delaware assignors to United States Rubber NewYork, N. Y., al corporation Application october 11, 1935, serial No.44,552

9 Claims.Y

Our invention relates to apparatus for cutting tire molds. Moreparticularly it relates to an adjustable stop ring and associatedmechanism for successively cutting irregular length units of treadconguration in a mold.

Recent developments in the manufacture of pneumatic tires have resultedin the adoption of tread configuration, wherein individual t-readelements or non-skid units are made in variable length in order to breakup sound producing vibrations while the tire is in operation. Forexample, a tread may be divided into units of tread elements havingvariable lengths such as 9, I 0, and I I. These various lengths may begrouped to form various combinations throughout the circumference of thetread.

A prior method of cutting a mold having such a tread configurationconsisted of cutting all of the tread units which were of equal length;as, for example, tread units 9. After these units were cut, a differentgear ratio was used in order to produce a longer tread unit such as IIJ.Then the tread units of length II were cut.

A machine operation of this kind has various objections. It is neitheraccurate nor efficient requiring changes during the machine operation,when results in much loss of time in a mold cutting operation. It is,therefore, an object of this invention to provide an expeditious andeconomical apparatus for cutting or engraving variable pitch treadunits.

A further object is to provide means for consecutively cutting treadconfigurations in a mold wherein the tread elements are of diierent unitlengths.

Fig. 2 is a perspective view, partly in section,

of a portion of the apparatus looking from a different angle;

Fig. 3 is a side elevational View of a mold engraving stop ring;

Fig. 4 is a developed view thereof;

Fig. 5 is a longitudinal view, in section, of

the mold engraving stop ring;

Fig. 6 is a longitudinal view, in section, of a modified form of a moldengraving stop ring;

Fig. 7 is a developed view thereof; Y Fig. 8 is transverse view, insection, of a Figs. 16 to 19, inclusive, are similar diagram-1 maticviews illustrating thefunction 'of the embodiments shown in Figs. 6, '7,and 8.

Referring to Figs. 1 and 2, we shoW a mold` engraving machine which forthegreater part consists of conventional apparatus. A frame I2 supportsa slide plate I3 onIwhich a mold table I4 is rotatable. A hand wheellvmounted on a shaft I 6 carries a bevel gear I'I which intermeshes withteeth on the under side of the mold table I4. A bracket I8 maintains thebevel gear I 'I in proper meshing relation Withthe gear teeth on theunder side of the mold table'IL As the mold engraving tool, hereinafterexplained, is maintained in fixed relative position, means is providedfor moving a mold I9 into and out of engagement with the'engravingtool.V This Y means comprises arack 20 secured to the under side of theslide plate I3, and meshing with aV gear 2| attached to a shaft 22. Ahand lever 23, also attached to the shaft 22, provides' means: formanually adjusting the horizontal position of the mold I9. A ratchetlatch 24 cooperates with the hand lever 23 for maintaining it in .afixed' position. Adjustable means, as a Vnut 25, is secured to a rod 26attached to the slide plate `I3 and extending through a lug 21 dependingfrom the frame I2. This limits the movement of thev mold I9 relative tothe engraving mechanism.

A horizontal bracket 28 extends from a vertical member 29 forming partof the frame I2, and isV adjustable for vertical movement by operationof a hand lever 33 associated with conventional means such as a wormscrew (not shown). The horizontal bracket 28 supports the engraving toolmechanism consisting of a pivoted shaft 3| carry-V ing an engraving orcutter tool 32."` A pulley 33 mounted on the opposite end of the shaft3| pro--V vides means through which the cutter tool 32 is operated.

In order to move the cutter tool 32 transverselyV across the crown ofthe tire mold, the shaft 3I through its housing support 34 is pivoted tothe horizontal bracket 28 at 35. VA gear segment 36 50 secured to thehousing 34 meshes withY a rack 31 (Fig. 2) attached to a plate 38slidably mounted on the horizontal bracket 28. Horizontal movement oftherack S'Iand plate 33 is effected by manual operation of a hand lever39 pivotally at. 55

tached at 4t to the horizontal bracket 28 and engaging with the plate 38at a pivot 4I.

As thus described, it is evident that thecutting tool may be moved toany point in the area of the crown of the tire mold. That is, manualoperation of the hand wheel l5 produces rotary movement of the tire moldI9, while manual operation of the hand lever 39 moves the working tool32 transversely across the crown of the tire mold I9;

Means in the form of a congured or slotted stop ring 42 is provided inorder to operate as a guide for limiting relativeY movement of ithecutting tool 32, and for preventing the moving of the tool 32 outside ofa predetermined pattern- In order to decrease the possibility of errorsyinV the engraving of the tread pattern the stop ring is usually providedwith a larger pattern than the actual size of the tread unit. Forexample, its ratio to the mold pattern is approximately 4 The stop ring42 is rotatable relative to rotary movement of the mold I9. This properrelation is maintained-through'a chain of gears 43, 44, and 45.

A bracket 46 which supports the gear 44 is adjustable in order tocompensate for diiferent heights of the horizontal bracket 28, and alsofor the purpose of accommodating substitute gears for providing correctrelative movements between the stop ring 442' and the mold I9.

The gear 45 is mounted' on a shaft 41 which also carries the stop ring42. During the normal operation of the engraving apparatus the stop ring42 is held in locked relation with the shaft 41, and a follower pin 48'retained in an extension 49 of the plate 38 is located over andcooperates with theV configuration or slot in the ring 42'. Theconiiguration in the ring 42 forms a depressed design of which the basediameter is less` than that of the stop' ring' properj and the pin 48 inengaging witli the smaller diameter of the configuration limits therotary movement of' the ring 42 in accordance with the pattern thereon.The stop ring, in turn, limits the horizontal movement of the pin' 48,thus` deni'ng'th'e movement of the working to'ol 32 relative tothe moldI9.

As thus` far explained, thestop ring and its associated mechanism willoperate to permit the engraving of atire mold, providing all of thetreadunitsrare of equal length. In the present invention, however, thering 42 is particularly adaptable for permitting the engraving of a moldwherein the tread units are of' variable length. This is effectedprincipally by permitting predeterminedv movement of the stop ring 42relative to the shaft 41'.

As shown in Fig. 5, the ring 42 is adjustably movable in rotary relationto ahub 50 secured to the shaft` 4-1 by meanssuch asa sert screw 5|. Acollar 52secured to the hub 59 operates to retain the ring 42 on the hub50. A pin 53 extends through the ringr 42 and engages with one of apluralityj of apertures 54 in the hub 58.

In Fig'. 3, a spring 55 is connected between the pin 53 anda screw 56on" the ring 42. This is merely a provision for preventing the loose pin53 'lov from dropping out of engagement with the ring l2 and hub 50`during rotary'movement thereof.

FigjlV shows a development of the stop ring 42 and hubV 50 and treadpattern unit 51.

In the present embodiment we show the tread unit pattern in rectangularform so as to-permit the engraving of a tread of the conventional block:type. However, it is to' be understood that the stop ring and treadconiguration may be of any other pattern such as diamond shaped units,multiple arrangements of rectangular units, or combinations of both.

As the tread units in the mold are cut, the mold is rotatedprogressively in the direction indicated by the arrow in Fig. 2.Corresponding to this movement, the stop ring, as shown in Fig. 4, movesprogressively forward as indicated by the directional arrow.

Figs. 9 to 15, inclusive illustrate a cycle of operation whereinadjacent differential blocklengths in a mold are cut-in the order ofI-9I l-li relative positions of the pin 48 and the cutting tool 32 beingshown.

Fig. 9 illustrates the first position in the cycle of operation, showingthe cutting of a number IG block length unit in a mold. The cutting ofthis block lo is determined from an index ring lil)y carried by the moldI9 cooperating with a pointer 6I carried by a bracket 28 which indicateson the ring that a number lil block unit is in,

order to`be cut. In this case the design 51 of the stop ringV 42 itselfis equivalent to the block length I0'. Therefore, it is only necessaryto cut the complete block outline in accordance with the pattern 5T ofthe ring 12.l The pin 53`which locks the stop ring 42 with the hubv 50may be placed adjacent any of the numerals indicated on the hub 55.However, in order to form a closer relationship, the block Alil is cutwith the pin 53y located adjacent to the numeral li! on the hub 59.

When the block I0 is completely cut the mold is rotated by the handwheel i5 (Fig. 2) to a position for the next block cutting operation. Asshown in Fig. IO, the index ring 68 indicates that the next cuttingoperation is a number 9 block length unit. The start of this operationis similar to the cutting of Va number Il! block unit. Th'at is, the pin48 (Fig. 2) is lifted up a'nd the stop ring 42 and hub 50 rotated adistance soV that the block I0 will be spaced, as show'n, a shortdistance from the subsequent block 9. This dis Y tance is determi'ned'bythe diameter of the stop ring 42` and' represents the circumferentialdistance between the ends of the stop ring pattern 5'1. After the ring42 has been rotatedv at least such a distance, the pin 48`is'dropped ina position within the outline of the stop ring pattern.

Itk will be noted that thus far the pin 53'has not been disturbed inrelation to the hub 50. At shown in Fig. 10, the length of'th'e'patte'rn' 51 is greater than the length of the block unit 9.A'ccordinglyybefore` thev stop'ring' 42 is changed in relation to thehub 50 any portion of the block 9 may be cut which is equal to or lessthan the length of block 9. However, in the practice' of the inventionit has' been foundv expedient to cut the forward portion of the blockfor about onehalf the lengthof the block pattern 51. At this stage ofthe operation, as shown in Fig. 11, pin 53 is raised and the stop ring42 is moved ahead (upwardly as shown in the drawings), the pin 53 beingreplaced in registry with the numeral 9 on the hub 50. This movement ofthe stop ring operates to shorten the remaining uncut portion of theblock unit 9 in the mold by advancing the rear edge of the pattern 51towards the tool 32.

Assuming that the next block unit is of number Il length, as' shown bythe index ring (Fig. 12), the pin 48 is moved over the bridge separatingthe ends of the pattern 51, and the first half or portionof number Ilfblock unit is cut'. Next pin 53 is raised and the stop ring 42 is moved.

as shown in Fig. 13, the remaining portion of the block length unit IIis cut. Thus, the backward movement of the stop ring 42, after a portionof the block has been cut, permits the cutting of ablock unit such as IIlonger than the total length of the pattern 51. If, as previouslyassumed, the next block length is also a number Y II unit, the firsthalf or portion of the block is cut as usual, as shown in Fig. 14.

Before cutting the remaining portion of the block the pin 53 is raised,and the stop ring 42 is moved backward so that the pin is taken out ofregistry with the numeral I on the hub 50 and placed in registry withthe numeral 2, as shown in Fig. 15.

From the foregoing it will be seen that the numerals I to I 6 on the hub50 have no particular significance relative to the exact block length ofany specific unit such as 9I6I I--I I, but that they serve as guides foridentifying the location of the pin 53. For example, if the pin 53 islocated in registry with the numeral 2 on the hub 50 for cutting a blockunit II and it is desired to next cut a block unit 9, pattern 51 isshortened by moving the stop ring forward two notches, thus bringing thepin 53 in registry with the numeral 4 on the hub 50. In this mannerconsecutive tread units may be engraved in which adjacent units are ofvarying length, and which may be selected according to predeterminedrequirements. It will be noted that in this stop ring construction it isrequired to cut about onehalf of the next adjacent tread configurationbefore the stop ring is adjusted in its final position. This isnecessary in order to maintain a uniform distance between adjacent treadpattern units. Y

. From the foregoing stop ring operation it will be noted in certaincases, particularly in cutting of a numeral such as a nine length treadunit, that only one part or halfof the stop-ring can be used at onesetting. In other words, the whole outline of the stop ring could not beused to out a numeral 9 length tread unit for the reason that thepattern 51 itself in its full length is equivalent to a I0 length treadunit. We therefore provide by way of modification a stop ring assemblycapable of operating as a guide for the cutting of a complete treadunit, regardless of its length. This modification is shown in particularin Figs. 6, 7, and 8. In general, it is sirnilar to the stop ringpreviously described, except that it is in the form of a double ring,each ring requiring separate adjustment.

This modified form of stop ring may be positioned on the shaft 41 (Fig.6), and comprises a hub 62 secured to the shaft 41 by means such as aset screw 63. 'I'he stop ring itself consists of an inner sleeve 64 andan outer sleeve 65. Each of these sleeves S4 and 65 includes asubstantially similar pattern 66, which in overlapping combination formbut a single effective tread unit pattern cooperating with pin 48.

The principal feature of this stop ring is that the length of theeffective pattern may be definitely controlled. The inner sleeve 64 isrotatable within the confines of a reduced diameter of the hub 62. Acollar 61 normally retains the inner sleeve 64 in its proper relation onthe hub 62. An aperture 68 through one wall of the inner sleeve 64, anda plurality of apertures 69 through the wall of the hub 62 and in spacedrelation therearound, provide means for inserting a pin 18 to lock theinner sleeve 64 in position with the hub 62. 'I'he outer sleeve 65 isrotatable about a reducedfdiameter formed in part bythe hub 62 Y and inpart by the inner sleeve-64. i 'The outerV sleeve 65 likewise has anaperture 1I extending through'the wall thereof for cooperative alignmentwith a plurality of apertures 12 radially p0- sitioned and in spacedrelation around the wallV of the hub 62. Pins 'I3l inserted into theapertures 1I and into one`of the apertures'12 ofthe hub 62 provide meansfor locking the outer sleeve 65 with the hub 62. 1 1

64 and 65 must each be equal in length'to the greatest length-0f theblock desired to be cut. The end of the pin 48 rests on the surfaceofthe hub 62 so that each of the sleeves 64 and 65 will operate to reactwith thepin 48, and so that the sleeves 64 and 65 in combination willVVform but a single effective tread pattern.

Diagrammatic illustrations shown in Figs. 16 to 19, inclusive, show acycle of operation for cutting successive cavities in molds; forexample, inthe length order of I I-I U49. In this modification thelongest block length is a number I I unit. This is indicated on theindex ring inlFig. 16 wherein the first block length I I is cut with thetwo sleeves 64 and 65 and their patterns radially superimposed, whichoccurs when the pins 13 and 16 are in registry with like numerals on thehub 62 and collar 61, respectively.` In Figs.

ends of the pattern 66 one of the sleeves such asj j 101 It ispreferable that the tread unit patterns 66 sleeve 64 Vis moved forwardto shorten the length f of the effective pattern from the number II unitlength to a number I 0 unit length. This shortening of the pattern iseffected by loosening theV pin 16 and moving sleeve 64 forward one notchso that the pin 10 is placed iniregistry with the numeral 9 on thecollar 61. The cavity forming the block I0 in the mold I9 may now becompletely cut according to the pattern 66.

cut it is necessary to place the stop ring in a neu- Y tral position orperfectly superimposedrposition,

the ends of the pattern 66, and the index ring, as shown in Fig. 19,indicates that the number 9 block unit is to be cut. I

As the stop Vring was previously set inthe normal or greatest lengthblock pattern, such as unit II, it is now necessary to shorten thepattern two notches so as toY forma number 9 unit length. This may beaccomplished by'movlngv the Y inner sleeve 64 forward two notches, `thusbring- 75:

Before the next adjacent cavity in the mold is 55 Y 65 Pin 48 is nextmoved over the bridge separating ing the pin 1U into` registry with. thenumeral=1 on the collar 6T-l Inthis modiedformof stop-ring any desiredpredetermined'length of tread conguration can be obtained, and theoutline of the patternron the stopring after adjustment will conform inall respects with the outlineof the tread configuration desired to beengraved into the `mold.

While we have shown and described certain present preferred embodimentsof our invention, it will be readily understood that othermodifications'maybemadetherein within the spiritof the invention and thescope of the appended claims.

Having thus described our invention, what we claim and desire to protectby Letters Patent isz- l.` In acutting machine, a materialv support, acuttingtool', means for causing relative movement therebetween, a stopring, comprising a plurality of independently adjustable memberscollectively providing a slot,V movable in synchronism with suchrelative movement and a follower cooperating the slot for controllingthe amount ofsuch movement.

2. Mold cutting apparatus comprising a table for supporting a mold, acutting tool, means for causing relative movementI therebetween, andmeans for controlling the amount of such movement comprising a stop ringhaving a slot the eifective length` of which is adjustable movable in`synchronism with such' relative movement, andA a follower for the slotwhereby successive mold cuts of different lengths-may be produced byAchanges-in the eiective length of the slot.

3.V Mold cutting-apparatus comprising a table for supporting amold, a`cutting tool, means for causing relative movement therebetween, andmeans for controllingthe amount of such movement. comprising a stopvring having separately adjustable members collectively providing anadjustable slot movable in synchronism with such relativeA movementyanda follower for the slot, wherebysuccessive mold cutsof dilerent lengthsmay be produced by changesv in the stop ring setting.

4., In a cutting machine, a shaft, a hub xedly mounted thereon anda stopring comprising a plurality of independently adjustable members,

to control the movement of: a: cutting tool and' a follower cooperatingwith the' slot and the tool under control.

'7. Control means for a cutting machinei comprising a shaft driven insynchronism with apart of. the cuttingmachine, an index fixedly mountedon the' shaft. and aslotted stopk ring: encircling said shaftandadjustably secured thereto in co.- operative relation to said indexwhereby the position ofi saidf slot ori said shaft maybe varied? asi'desired.

8. Controlmeansfor a cutting machine comprising1a` shaft drivenk insynclfironisniv with a; part of the cutting machine, an index flxedlymounted on the shaft, a slotted stop ring encircling said shaft andadjustably secured thereto in cooperativeA relation to. saidindexwhereby the position of said slot on said shaft may be varied asdesired, and a follower cooperating witl'r the slot and the machine forcontrolling; the latter in accordance with the motion of said'stop ring.

9. Control means for a cutting machine comprising a shaft' drivenin-synchronism with a a part of lthe cutting machine, an index xedlymounted' on the shaft, a pair of superimposed slotted members encirclingsaid shaft and adjustably secured thereto in cooperative relation tosaid index, whereby the positions of said members relativeto each otherand the shaft may be adjusted to provide a resultant slot, and afollower cooperating with the slot and the machine for controlling thelatter in accordance with the motion of said cooperating slottedmembers.

LISLE M. WATSON. RAYMOND F. TERNES'. LESTER G. BUDLONGf.y

